Distal-less homeobox-1 (DLX1) is a well-established non-invasive biomarker for prostate cancer (PCa) diagnosis, however, its mechanistic underpinnings in disease pathobiology are not known. Here, we ...reveal the oncogenic role of DLX1 and show that abrogating its function leads to reduced tumorigenesis and metastases. We observed that ~60% of advanced-stage and metastatic patients display higher DLX1 levels. Moreover, ~96% of TMPRSS2-ERG fusion-positive and ~70% of androgen receptor (AR)-positive patients show elevated DLX1, associated with aggressive disease and poor survival. Mechanistically, ERG coordinates with enhancer-bound AR and FOXA1 to drive transcriptional upregulation of DLX1 in ERG-positive background. However, in ERG-negative context, AR/AR-V7 and FOXA1 suffice to upregulate DLX1. Notably, inhibiting ERG/AR-mediated DLX1 transcription using BET inhibitor (BETi) or/and anti-androgen drugs reduce its expression and downstream oncogenic effects. Conclusively, this study establishes DLX1 as a direct-target of ERG/AR with an oncogenic role and demonstrates the clinical significance of BETi and anti-androgens for DLX1-positive patients.
Emergence of an aggressive androgen receptor (AR)-independent neuroendocrine prostate cancer (NEPC) after androgen-deprivation therapy (ADT) is well-known. Nevertheless, the majority of ...advanced-stage prostate cancer patients, including those with SPINK1-positive subtype, are treated with AR-antagonists. Here, we show AR and its corepressor, REST, function as transcriptional-repressors of SPINK1, and AR-antagonists alleviate this repression leading to SPINK1 upregulation. Increased SOX2 expression during NE-transdifferentiation transactivates SPINK1, a critical-player for maintenance of NE-phenotype. SPINK1 elicits epithelial-mesenchymal-transition, stemness and cellular-plasticity. Conversely, pharmacological Casein Kinase-1 inhibition stabilizes REST, which in cooperation with AR causes SPINK1 transcriptional-repression and impedes SPINK1-mediated oncogenesis. Elevated levels of SPINK1 and NEPC markers are observed in the tumors of AR-antagonists treated mice, and in a subset of NEPC patients, implicating a plausible role of SPINK1 in treatment-related NEPC. Collectively, our findings provide an explanation for the paradoxical clinical-outcomes after ADT, possibly due to SPINK1 upregulation, and offers a strategy for adjuvant therapies.
Six transmembrane epithelial antigen of the prostate 1 (STEAP1) is a cell surface antigen for therapeutic targeting in prostate cancer. Here, we report broad expression of STEAP1 relative to ...prostate-specific membrane antigen (PSMA) in lethal metastatic prostate cancers and the development of a STEAP1-directed chimeric antigen receptor (CAR) T cell therapy. STEAP1 CAR T cells demonstrate reactivity in low antigen density, antitumor activity across metastatic prostate cancer models, and safety in a human STEAP1 knock-in mouse model. STEAP1 antigen escape is a recurrent mechanism of treatment resistance and is associated with diminished tumor antigen processing and presentation. The application of tumor-localized interleukin-12 (IL-12) therapy in the form of a collagen binding domain (CBD)-IL-12 fusion protein combined with STEAP1 CAR T cell therapy enhances antitumor efficacy by remodeling the immunologically cold tumor microenvironment of prostate cancer and combating STEAP1 antigen escape through the engagement of host immunity and epitope spreading.
Inter- and intra-patient molecular heterogeneity of primary and metastatic prostate cancer (PCa) confers variable clinical outcome and poses a formidable challenge in disease management. ...High-throughput integrative genomics and functional approaches have untangled the complexity involved in this disease and revealed a spectrum of diverse aberrations prevalent in various molecular subtypes, including ETS fusion negative. Emerging evidence indicates that SPINK1 upregulation, mutations in epigenetic regulators or chromatin modifiers, and SPOP are associated with the ETS-fusion negative subtype. Additionally, patients with defects in a DNA-repair pathway respond to poly-(ADP-ribose)-polymerase (PARP) inhibition therapies. Furthermore, a new class of immunogenic subtype defined by CDK12 biallelic loss has also been identified in ETS-fusion-negative cases. This review focuses on the emerging molecular underpinnings driving key oncogenic aberrations and advancements in therapeutic strategies of this disease.
Several distinct subtypes marked by germline or somatic mutations, gene fusions, focal deletions, and amplifications have been identified in the ETS-fusion-negative subtype.Novel regulatory mechanisms underlying increased SPINK1 levels, include: (i) AR-mediated transcriptional repression of SPINK1; (ii) EZH2-mediated epigenetic silencing of miR-338-5p/miR-421; and (iii) negative post-transcriptional regulators of SPINK1.Aberrations in epigenetic regulators or chromatin remodelers, ubiquitin, and spliceosome machineries represent novel subclasses of ETS-fusion-negative PCa.Mutations in DNA damage and repair genes sensitize PCa cells to PARP inhibition, increases neoantigens and T cell infiltration, hence sensitizing them towards immune checkpoint inhibitors.Sequentially collected liquid biopsies support identification of therapy-resistant clones, and reveal the mechanism involved in tumor evolution.
Prostate-specific membrane antigen (PSMA) is an important cell surface target in prostate cancer. There are limited data on the heterogeneity of PSMA tissue expression in metastatic ...castration-resistant prostate cancer (mCRPC). Furthermore, the mechanisms regulating PSMA expression (encoded by the FOLH1 gene) are not well understood. Here, we demonstrate that PSMA expression is heterogeneous across different metastatic sites and molecular subtypes of mCRPC. In a rapid autopsy cohort in which multiple metastatic sites per patient were sampled, we found that 13 of 52 (25%) cases had no detectable PSMA and 23 of 52 (44%) cases showed heterogeneous PSMA expression across individual metastases, with 33 (63%) cases harboring at least 1 PSMA-negative site. PSMA-negative tumors displayed distinct transcriptional profiles with expression of druggable targets such as MUC1. Loss of PSMA was associated with epigenetic changes of the FOLH1 locus, including gain of CpG methylation and loss of histone 3 lysine 27 (H3K27) acetylation. Treatment with histone deacetylase (HDAC) inhibitors reversed this epigenetic repression and restored PSMA expression in vitro and in vivo. Collectively, these data provide insights into the expression patterns and regulation of PSMA in mCRPC and suggest that epigenetic therapies - in particular, HDAC inhibitors - can be used to augment PSMA levels.
Conrad Waddington’s theory of epigenetic landscape epitomize the process of cell fate and cellular decision-making during development. Wherein the epigenetic code maintains patterns of gene ...expression in pluripotent and differentiated cellular states during embryonic development and differentiation. Over the years disruption or reprogramming of the epigenetic landscape has been extensively studied in the course of cancer progression. Cellular dedifferentiation being a key hallmark of cancer allow us to take cues from the biological processes involving epigenetic reprogramming in development such as the cellular differentiation and morphogenesis. Here, we discuss the role of epigenetic landscape and its modifiers in cell-fate determination, differentiation and prostate cancer progression. Lately, the emergence of RNA-modifications has also furthered our understanding of epigenetics in cancer. The overview of the epigenetic code regulating androgen signalling, and progression to aggressive neuroendocrine stage of PCa reinforces its gene regulatory functions during the development of prostate gland as well as cancer progression. Additionally, we also highlight the clinical implications of cancer cell epigenome, and discuss the recent advancements in the therapeutic strategies targeting the advanced stage disease.
Serine peptidase inhibitor, Kazal type-1 (SPINK1) overexpression defines the second most recurrent and aggressive prostate cancer subtype. However, the underlying molecular mechanism and pathobiology ...of SPINK1 in prostate cancer remains largely unknown.
miRNA prediction tools were employed to examine the
3'UTR for miRNA binding. Luciferase reporter assays were performed to confirm the
3'UTR binding of shortlisted miR-338-5p/miR-421. Furthermore, miR-338-5p/-421-overexpressing cancer cells (SPINK1-positive) were evaluated for oncogenic properties using cell-based functional assays and a mouse xenograft model. Global gene expression profiling was performed to unravel the biological pathways altered by miR-338-5p/-421. IHC and RNA
hybridization were carried out on prostate cancer patients' tissue microarray for SPINK1 and
expression, respectively. Chromatin immunoprecipitation assay was performed to examine EZH2 occupancy on the miR-338-5p/-421-regulatory regions. Bisulfite sequencing and methylated DNA immunoprecipitation were performed on prostate cancer cell lines and patients' specimens.
We established a critical role of miRNA-338-5p/-421 in posttranscriptional regulation of
. Ectopic expression of miRNA-338-5p/-421 in SPINK1-positive cells abrogates oncogenic properties including cell-cycle progression, stemness, and drug resistance, and shows reduced tumor burden and distant metastases in a mouse model. Importantly, we show that patients with SPINK1-positive prostate cancer exhibit increased EZH2 expression, suggesting its role in epigenetic silencing of miRNA-338-5p/-421. Furthermore, presence of CpG dinucleotide DNA methylation marks on the regulatory regions of miR-338-5p/-421 in SPINK1-positive prostate cancer cells and patients' specimens confirms epigenetic silencing.
Our findings revealed that miRNA-338-5p/-421 are epigenetically silenced in SPINK1-positive prostate cancer, although restoring the expression of these miRNAs using epigenetic drugs or synthetic mimics could abrogate SPINK1-mediated oncogenesis.
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Though stress can affect the incidence and severity of periodontal diseases, but the association is indirect in most of the cases as rightly acknowledged by the authors. Since the relationship of ...stress and periodontal diseases has comprehensively been reviewed here, we would like to make a sincere mention of some suggestions, which can have a lasting impact on patient's care:
Sepsis results in 270,000 deaths annually in the United States. Despite the current healthcare focus on sepsis, there exist few postacute best-practice standards to rapidly identify health changes in ...home healthcare patients to prevent and reduce hospital readmissions due to sepsis. We systematically examined whether an evidence-based process and intervention triggering home healthcare clinicians to activate a Positive Sepsis Assessment would reduce the likelihood that the patient would be readmitted to the acute care hospital. Over 24 months, we tracked the rate of sepsis readmissions to acute care hospitals through the initial phase of early recognition education; assessment, review, and revision of best-practice algorithms; standardized documentation; and proactive care management, in conjunction with the patient's primary care provider. During our review of the last 12 months of data on home care patients triggering the Positive Sepsis Assessment 130 patients were identified to have potential signs of sepsis. Ninety-seven of these patients received early medical intervention in place and were not readmitted to the hospital. Our findings suggest that a multidisciplinary home healthcare team utilizing standard sepsis education and sepsis algorithm on every patient during every visit can reduce and prevent readmissions.
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